There is no way of having the cabin assigned until the cruiseline issues the cabins. Well, I take that back. You can always pay a higher rate for an assigned cabin. The reason for the lower promotional rates on Guar status cabins is so the cruiseline can assign you whatever they have left after the people who pay add'l to choose have made their choices. Many people are willing to pay more to choose their deck or have cabins side by side for families and groups traveling together. You pay less but don't get to choose. You also increase your odds of complimentray upgrades if you take a guar cabin. I do it frequently.